waters over 30 °C. Critical thermal maximum temperatures of the species show a lower threshold for juveniles than adults. E. nana are often found along the river substrates, such as rocks and vegetation. The uppermost shallow portion of Spring Lake features sand, gravel, and large limestone boulders that provide habitat. Further down, concrete banks and boulders provide space for aquatic moss such as L. riparium and blue-green algae. A variety of aquatic macrophytes, including S. platyphylla, M. brasiliense, L. repens, and V. americana are also present. Substrates without vegetation and muddy slit areas are unsuitable for E. nana, as those serve as protective covers against predation from larger fish, turtles, and aquatic birds. Diet The diet of E. nana includes amphipods, fly larvae, and aquatic snails. San Marcos Salamanders typically follow a temporal diet, or a diet that varies with the availability of invertebrates present to them at a given time. It relies on the schedule of invertebrate behavior and locations, and generally consumes many aquatic invertebrates. The surrounding vegetation is a rich source of food. Behavior E. nana displays predator avoidance responses relying on chemical cues from its native predators, such as Micropterus salmoides. Antipredator responses include freezing behavior to its fish predators. Site tenacity, the pattern of returning to the same nest or breeding site dependent on the season, was observed in both males and females of E. nana. This suggests that there is a selection favoring aggregation and shelter use as a part of anti-predatory tactics. Lab results show that predator-naïve salamanders showed a greater reduction in activity compared to predator-experienced salamanders, suggesting behavioral plasticity in avoidance responses. E. nana are also known to show predator generalization in response to novel predators similar to native ones. The E. nana response to their crayfish predators is unknown and studies to answer this question are currently ongoing. The feeding behavior of the salamander is rather passive as it waits for prey to pass and will abruptly snap forward to catch its food. This suggests this response is likely generated from visual or vibrational cues from prey. The San Marcos salamander breeds and lays eggs in standing ponds in the middle of dense mats of aquatic vegetation. Eggs are jelly-covered and will hatch in about 24 days. Male E. nana reaches maturity with a snout-vent greater than 19 mm. Four classes of ova are present: small-clear ova, small-opaque ova, small-yellow